Key duplicating machines of mechanical type are known, provided with a feeler which is made to slide along the profile of the original key to be duplicated, clamped in a first clamp, and with a milling cutter rigid with the feeler and acting on the blank key to be bitted, clamped in a second clamp fixed relative to the first.
Electronic duplicating machines are also known, which instead of the feeler use an optical reader for the key bitting pattern; in particular, the optical reader comprises a light source facing the original key and a sensor which collects the rays emitted by said source and traversing the bitted portion of the key. These machines also require the presence of two clamps, one for the blank key to be bitted, facing the milling cutter, and one for the original key to be duplicated, facing the optical reader. The two clamps are mutually rigid and are movable relative to the optical reader and to the milling cutter, which are fixed relative to the machine base.
A drawback of these known electronic duplicating machines is their large overall size; in addition the result of this duplication can be influenced by the different manufacturing errors, inevitably existing between the two clamps, and the errors in positioning the two keys therein. Again there is the fact that a preliminary and laborious aligning operation between the two clamps has to be carried out such that the original key and the blank key clamped thereby are both positioned with their axes rigorously parallel to each other.
WO 99/06179 describes an electronic key duplicating machine in which the key is retained at its head by suitable tabs. The optical reader and milling cutter are mounted on a rotary discoidal support which is suitably rotated such that the optical reader or milling cutter face the key at different moments.